Lubricating oil or lubricating additive is adopted as a buffer lubrication medium of a common cartridge when the cartridge rotates. But a method in which lubricating oil is adopted has the defects, such as complicated process and easy pollution, and thus cannot meet the actual needs of consumption. Therefore, the production enterprises adopt an oil-free cartridge structure instead of a traditional cartridge. However, the existing oil-free cartridge is relatively complicated in structure and inconvenient to dismount during production or use because of the use of more components, and the complicated component structure further improves the production cost, increases the economic burden of consumers and is not conductive to product promotion.